2D WS2 monolayer preparation method and research progress in the field of optoelectronics

Two-dimensional transition metal dichalcogenides (2D TMDs) have attracted considerable interest in materials science due to their exceptional electronic and optoelectronic characteristics, such as high carrier mobility and adjustable band gaps. Although extensive studies have been conducted on various TMDs, a significant gap persists in the understanding of synthesis methods and their effects on the practical use of monolayer tungsten disulfide (WS2) in optoelectronic devices. This gap is crucial, as the effective incorporation of WS2 into commercial applications relies on the establishment of dependable synthesis techniques that guarantee the material's high quality and uniformity. In this review, we provide a detailed examination of the synthesis methods for monolayer WS2, emphasizing mechanical stripping, atomic layer deposition (ALD), and chemical vapor deposition (CVD). We discuss the benefits of each technique, including the uniform growth achievable with ALD at lower temperatures and the ability of CVD to generate large-area, high-quality monolayer. Furthermore, we review the performance of WS2 in various electronic and optoelectronic applications, such as field-effect transistors, photodetectors, and logic devices. Our review suggest that ongoing improvements in film uniformity, compatibility with current semiconductor processes, and the long-term stability of WS2-based devices indicate a promising pathway for transitioning 2D WS2 from laboratory settings to practical applications.